There is a paucity of information on late life bipolar disorder. Unlike bipolar disorder in the young, familial factors are less important in the elderly. In fact, available data suggests that elderly bipolar patients are a distinct group. Vascular factors may be of more importance than genetic factors in the development of bipolar disorder in late life. We have in the last four years developed information on MRI changes, clinical features, and retrospective data on treatment response of elderly bipolar subjects compared with younger bipolar subjects and age-matched controls. Further, our preliminary data utilizing DTI has suggested structural changes in the frontal regions of multi-aged bipolar patients. In this renewal we aim to obtain data on the course and outcome of bipolar disorder, as well as to extend our understanding of MRI/DTI changes by characterizing the location of these changes, their impact on the fibre tracts connecting the frontal and striatal cortex and evaluating the course of response and the effect of MRI changes on treatment outcome. This research is unique and is likely to enhance our understanding of the phenomenology, course, outcome and relationship of MRI changes to the pathophysiology of bipolar disorder in late life.